From 1723e1bedb9545c45619c4023729755243524584 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Mon, 25 Nov 2019 13:42:49 +0000 Subject: [PATCH] Properly handle C2x attributes on types. attribs.c has code to ignore all scoped attributes appertaining to types except when they are part of the definition of that type. I think the premise of that code is incorrect, and its presence is a bug; such attributes are clearly valid in both C and C++, which explicitly specify that attributes in certain syntactic positions appertain to a particular type, only for that use of that type and not for other uses of the same type specifiers without that attribute specified, and while the standard attributes in C2x aren't relevant in such contexts, some gnu:: attributes certainly are. Where some attributes are invalid on some types in such contexts, that's a matter for the individual attribute handlers to diagnose (or the front end if the requirements on a standard attribute in the standard are more strict than those of a handler shared with a GNU attribute). Thus, this patch removes the bogus code to allow such attributes to be used. Doing so (and adding tests for attributes in such positions) shows up that the logic in the C front end for creating the c_declarator structures for such attributes put them in the wrong place relative to the structures for function and array types, and the logic for postfix attributes on a list of declaration specifiers failed to handle some cases, so those bugs are also fixed in this patch. Bootstrapped with no regressions for x86_64-pc-linux-gnu. gcc: * attribs.c (decl_attributes): Do not ignore C++11 attributes on types. gcc/c: * c-tree.h (struct c_declarator): Use a structure for id member. * c-decl.c (grokdeclarator): Extract attributes from cdk_id declarators at the start, not when handling individual declarators later. Use u.id.id instead of u.id. (grokfield): Use u.id.id instead of u.id. (build_id_declarator): Set u.id.id and u.id.attrs. (finish_declspecs): Handle postfix attributes in case of typedef name or typeof used. * c-parser.c (c_parser_direct_declarator) (c_parser_direct_declarator_inner): Place declarator for attributes inside that for function or array, not outside. Set u.id.attrs for identifiers. (c_parser_parameter_declaration): Use u.id.id instead of u.id. * gimple-parser.c (c_parser_gimple_declaration): Use u.id.id instead of u.id. gcc/testsuite: * gcc.dg/gnu2x-attrs-1.c: Do not expect message about attributes appertaining to types. * gcc.dg/gnu2x-attrs-2.c: New test. * g++.dg/cpp0x/gen-attrs-1.C, g++.dg/cpp0x/gen-attrs-22.C, g++.dg/cpp0x/gen-attrs-4.C, g++.dg/cpp0x/lambda/lambda-attr1.C: Update expected diagnostics. From-SVN: r278683 --- gcc/ChangeLog | 5 ++ gcc/attribs.c | 15 ----- gcc/c/ChangeLog | 18 ++++++ gcc/c/c-decl.c | 55 ++++++++++--------- gcc/c/c-parser.c | 17 ++---- gcc/c/c-tree.h | 12 +++- gcc/c/gimple-parser.c | 4 +- gcc/testsuite/ChangeLog | 9 +++ gcc/testsuite/g++.dg/cpp0x/gen-attrs-1.C | 2 +- gcc/testsuite/g++.dg/cpp0x/gen-attrs-22.C | 2 +- gcc/testsuite/g++.dg/cpp0x/gen-attrs-4.C | 2 +- .../g++.dg/cpp0x/lambda/lambda-attr1.C | 2 +- gcc/testsuite/gcc.dg/gnu2x-attrs-1.c | 3 +- gcc/testsuite/gcc.dg/gnu2x-attrs-2.c | 33 +++++++++++ 14 files changed, 115 insertions(+), 64 deletions(-) create mode 100644 gcc/testsuite/gcc.dg/gnu2x-attrs-2.c diff --git a/gcc/ChangeLog b/gcc/ChangeLog index b0957b0f973..58be9e9410b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +2019-11-25 Joseph Myers + + * attribs.c (decl_attributes): Do not ignore C++11 attributes on + types. + 2019-11-25 Bernd Schmidt * config/m68k/m68k.c (output_move_himode, output_move_qimode): diff --git a/gcc/attribs.c b/gcc/attribs.c index de34918919b..0519f075ece 100644 --- a/gcc/attribs.c +++ b/gcc/attribs.c @@ -593,21 +593,6 @@ decl_attributes (tree *node, tree attributes, int flags, } gcc_assert (is_attribute_p (spec->name, name)); - if (TYPE_P (*node) - && cxx11_attr_p - && !(flags & ATTR_FLAG_TYPE_IN_PLACE)) - { - /* This is a c++11 attribute that appertains to a - type-specifier, outside of the definition of, a class - type. Ignore it. */ - auto_diagnostic_group d; - if (warning (OPT_Wattributes, "attribute ignored")) - inform (input_location, - "an attribute that appertains to a type-specifier " - "is ignored"); - continue; - } - if (spec->decl_required && !DECL_P (*anode)) { if (flags & ((int) ATTR_FLAG_DECL_NEXT diff --git a/gcc/c/ChangeLog b/gcc/c/ChangeLog index cb1ea0948dd..9f0b8cee6eb 100644 --- a/gcc/c/ChangeLog +++ b/gcc/c/ChangeLog @@ -1,3 +1,21 @@ +2019-11-25 Joseph Myers + + * c-tree.h (struct c_declarator): Use a structure for id member. + * c-decl.c (grokdeclarator): Extract attributes from cdk_id + declarators at the start, not when handling individual declarators + later. Use u.id.id instead of u.id. + (grokfield): Use u.id.id instead of u.id. + (build_id_declarator): Set u.id.id and u.id.attrs. + (finish_declspecs): Handle postfix attributes in case of typedef + name or typeof used. + * c-parser.c (c_parser_direct_declarator) + (c_parser_direct_declarator_inner): Place declarator for + attributes inside that for function or array, not outside. Set + u.id.attrs for identifiers. + (c_parser_parameter_declaration): Use u.id.id instead of u.id. + * gimple-parser.c (c_parser_gimple_declaration): Use u.id.id + instead of u.id. + 2019-11-22 Jakub Jelinek PR c/90677 diff --git a/gcc/c/c-decl.c b/gcc/c/c-decl.c index 7fd3cc26e87..a14f7821d1e 100644 --- a/gcc/c/c-decl.c +++ b/gcc/c/c-decl.c @@ -5951,6 +5951,7 @@ grokdeclarator (const struct c_declarator *declarator, bool array_parm_static = false; bool array_parm_vla_unspec_p = false; tree returned_attrs = NULL_TREE; + tree decl_id_attrs = NULL_TREE; bool bitfield = width != NULL; tree element_type; tree orig_qual_type = NULL; @@ -6013,8 +6014,9 @@ grokdeclarator (const struct c_declarator *declarator, case cdk_id: loc = decl->id_loc; - if (decl->u.id) - name = decl->u.id; + if (decl->u.id.id) + name = decl->u.id.id; + decl_id_attrs = decl->u.id.attrs; if (first_non_attr_kind == cdk_attrs) first_non_attr_kind = decl->kind; decl = 0; @@ -6300,7 +6302,9 @@ grokdeclarator (const struct c_declarator *declarator, Standard attributes applied to a function or array declarator apply exactly to that type; standard attributes applied to the identifier apply to the - declaration rather than to the type. */ + declaration rather than to the type, and are specified + using a cdk_id declarator rather than using + cdk_attrs. */ inner_decl = declarator; while (inner_decl->kind == cdk_attrs) inner_decl = inner_decl->declarator; @@ -6313,16 +6317,10 @@ grokdeclarator (const struct c_declarator *declarator, else if (inner_decl->kind == cdk_array) attr_flags |= (int) ATTR_FLAG_ARRAY_NEXT; } - if (cxx11_attribute_p (attrs) && inner_decl->kind == cdk_id) - returned_attrs = chainon (returned_attrs, attrs); - else - { - attrs = c_warn_type_attributes (attrs); - returned_attrs = decl_attributes (&type, - chainon (returned_attrs, - attrs), - attr_flags); - } + attrs = c_warn_type_attributes (attrs); + returned_attrs = decl_attributes (&type, + chainon (returned_attrs, attrs), + attr_flags); break; } case cdk_array: @@ -6883,6 +6881,7 @@ grokdeclarator (const struct c_declarator *declarator, } } *decl_attrs = chainon (returned_attrs, *decl_attrs); + *decl_attrs = chainon (decl_id_attrs, *decl_attrs); /* Now TYPE has the actual type, apart from any qualifiers in TYPE_QUALS. */ @@ -7017,7 +7016,7 @@ grokdeclarator (const struct c_declarator *declarator, type = c_build_qualified_type (type, type_quals, orig_qual_type, orig_qual_indirect); decl = build_decl (declarator->id_loc, - TYPE_DECL, declarator->u.id, type); + TYPE_DECL, declarator->u.id.id, type); if (declspecs->explicit_signed_p) C_TYPEDEF_EXPLICITLY_SIGNED (decl) = 1; if (declspecs->inline_p) @@ -7025,9 +7024,9 @@ grokdeclarator (const struct c_declarator *declarator, if (declspecs->noreturn_p) pedwarn (loc, 0,"typedef %q+D declared %<_Noreturn%>", decl); - if (warn_cxx_compat && declarator->u.id != NULL_TREE) + if (warn_cxx_compat && declarator->u.id.id != NULL_TREE) { - struct c_binding *b = I_TAG_BINDING (declarator->u.id); + struct c_binding *b = I_TAG_BINDING (declarator->u.id.id); if (b != NULL && b->decl != NULL_TREE @@ -7159,7 +7158,7 @@ grokdeclarator (const struct c_declarator *declarator, type = c_build_qualified_type (type, type_quals); decl = build_decl (declarator->id_loc, - PARM_DECL, declarator->u.id, type); + PARM_DECL, declarator->u.id.id, type); if (size_varies) C_DECL_VARIABLE_SIZE (decl) = 1; C_ARRAY_PARAMETER (decl) = array_parameter_p; @@ -7221,9 +7220,9 @@ grokdeclarator (const struct c_declarator *declarator, type = c_build_qualified_type (type, type_quals, orig_qual_type, orig_qual_indirect); decl = build_decl (declarator->id_loc, - FIELD_DECL, declarator->u.id, type); + FIELD_DECL, declarator->u.id.id, type); DECL_NONADDRESSABLE_P (decl) = bitfield; - if (bitfield && !declarator->u.id) + if (bitfield && !declarator->u.id.id) { TREE_NO_WARNING (decl) = 1; DECL_PADDING_P (decl) = 1; @@ -7259,7 +7258,7 @@ grokdeclarator (const struct c_declarator *declarator, } decl = build_decl (declarator->id_loc, - FUNCTION_DECL, declarator->u.id, type); + FUNCTION_DECL, declarator->u.id.id, type); decl = build_decl_attribute_variant (decl, decl_attr); if (type_quals & TYPE_QUAL_ATOMIC) @@ -7304,7 +7303,7 @@ grokdeclarator (const struct c_declarator *declarator, /* Record presence of `inline' and `_Noreturn', if it is reasonable. */ - if (flag_hosted && MAIN_NAME_P (declarator->u.id)) + if (flag_hosted && MAIN_NAME_P (declarator->u.id.id)) { if (declspecs->inline_p) pedwarn (loc, 0, "cannot inline function %"); @@ -7345,8 +7344,8 @@ grokdeclarator (const struct c_declarator *declarator, the 'extern' declaration is taken to refer to that decl.) */ if (extern_ref && current_scope != file_scope) { - tree global_decl = identifier_global_value (declarator->u.id); - tree visible_decl = lookup_name (declarator->u.id); + tree global_decl = identifier_global_value (declarator->u.id.id); + tree visible_decl = lookup_name (declarator->u.id.id); if (global_decl && global_decl != visible_decl @@ -7357,7 +7356,7 @@ grokdeclarator (const struct c_declarator *declarator, } decl = build_decl (declarator->id_loc, - VAR_DECL, declarator->u.id, type); + VAR_DECL, declarator->u.id.id, type); if (size_varies) C_DECL_VARIABLE_SIZE (decl) = 1; @@ -8009,7 +8008,7 @@ grokfield (location_t loc, { tree value; - if (declarator->kind == cdk_id && declarator->u.id == NULL_TREE + if (declarator->kind == cdk_id && declarator->u.id.id == NULL_TREE && width == NULL_TREE) { /* This is an unnamed decl. @@ -10295,7 +10294,8 @@ build_id_declarator (tree ident) struct c_declarator *ret = XOBNEW (&parser_obstack, struct c_declarator); ret->kind = cdk_id; ret->declarator = 0; - ret->u.id = ident; + ret->u.id.id = ident; + ret->u.id.attrs = NULL_TREE; /* Default value - may get reset to a more precise location. */ ret->id_loc = input_location; return ret; @@ -11468,7 +11468,7 @@ finish_declspecs (struct c_declspecs *specs) /* Set a dummy type. */ if (TREE_CODE (specs->type) == ERROR_MARK) specs->type = integer_type_node; - return specs; + goto handle_postfix_attrs; } /* If none of "void", "_Bool", "char", "int", "float" or "double" @@ -11729,6 +11729,7 @@ finish_declspecs (struct c_declspecs *specs) default: gcc_unreachable (); } + handle_postfix_attrs: if (specs->type != NULL) { specs->postfix_attrs = c_warn_type_attributes (specs->postfix_attrs); diff --git a/gcc/c/c-parser.c b/gcc/c/c-parser.c index 03194b438f2..5aa42e27801 100644 --- a/gcc/c/c-parser.c +++ b/gcc/c/c-parser.c @@ -3857,11 +3857,7 @@ c_parser_direct_declarator (c_parser *parser, bool type_seen_p, c_dtr_syn kind, inner->id_loc = c_parser_peek_token (parser)->location; c_parser_consume_token (parser); if (c_parser_nth_token_starts_std_attributes (parser, 1)) - { - tree std_attrs = c_parser_std_attribute_specifier_sequence (parser); - if (std_attrs) - inner = build_attrs_declarator (std_attrs, inner); - } + inner->u.id.attrs = c_parser_std_attribute_specifier_sequence (parser); return c_parser_direct_declarator_inner (parser, *seen_id, inner); } @@ -3898,9 +3894,7 @@ c_parser_direct_declarator (c_parser *parser, bool type_seen_p, c_dtr_syn kind, return NULL; else { - inner - = build_function_declarator (args, - build_id_declarator (NULL_TREE)); + inner = build_id_declarator (NULL_TREE); if (!(args->types && args->types != error_mark_node && TREE_CODE (TREE_VALUE (args->types)) == IDENTIFIER_NODE) @@ -3911,6 +3905,7 @@ c_parser_direct_declarator (c_parser *parser, bool type_seen_p, c_dtr_syn kind, if (std_attrs) inner = build_attrs_declarator (std_attrs, inner); } + inner = build_function_declarator (args, inner); return c_parser_direct_declarator_inner (parser, *seen_id, inner); } @@ -4028,7 +4023,6 @@ c_parser_direct_declarator_inner (c_parser *parser, bool id_present, static_seen, star_seen); if (declarator == NULL) return NULL; - inner = set_array_declarator_inner (declarator, inner); if (c_parser_nth_token_starts_std_attributes (parser, 1)) { tree std_attrs @@ -4036,6 +4030,7 @@ c_parser_direct_declarator_inner (c_parser *parser, bool id_present, if (std_attrs) inner = build_attrs_declarator (std_attrs, inner); } + inner = set_array_declarator_inner (declarator, inner); return c_parser_direct_declarator_inner (parser, id_present, inner); } else if (c_parser_next_token_is (parser, CPP_OPEN_PAREN)) @@ -4052,7 +4047,6 @@ c_parser_direct_declarator_inner (c_parser *parser, bool id_present, return NULL; else { - inner = build_function_declarator (args, inner); if (!(args->types && args->types != error_mark_node && TREE_CODE (TREE_VALUE (args->types)) == IDENTIFIER_NODE) @@ -4063,6 +4057,7 @@ c_parser_direct_declarator_inner (c_parser *parser, bool id_present, if (std_attrs) inner = build_attrs_declarator (std_attrs, inner); } + inner = build_function_declarator (args, inner); return c_parser_direct_declarator_inner (parser, id_present, inner); } } @@ -4352,7 +4347,7 @@ c_parser_parameter_declaration (c_parser *parser, tree attrs, c_declarator *id_declarator = declarator; while (id_declarator && id_declarator->kind != cdk_id) id_declarator = id_declarator->declarator; - location_t caret_loc = (id_declarator->u.id + location_t caret_loc = (id_declarator->u.id.id ? id_declarator->id_loc : start_loc); location_t param_loc = make_location (caret_loc, start_loc, end_loc); diff --git a/gcc/c/c-tree.h b/gcc/c/c-tree.h index dffefa3fd1a..cdfb9080346 100644 --- a/gcc/c/c-tree.h +++ b/gcc/c/c-tree.h @@ -460,9 +460,15 @@ struct c_declarator { /* Except for cdk_id, the contained declarator. For cdk_id, NULL. */ struct c_declarator *declarator; union { - /* For identifiers, an IDENTIFIER_NODE or NULL_TREE if an abstract - declarator. */ - tree id; + /* For identifiers. */ + struct { + /* An IDENTIFIER_NODE, or NULL_TREE if an abstract + declarator. */ + tree id; + /* Any attributes (which apply to the declaration rather than to + the type described by the outer declarators). */ + tree attrs; + } id; /* For functions. */ struct c_arg_info *arg_info; /* For arrays. */ diff --git a/gcc/c/gimple-parser.c b/gcc/c/gimple-parser.c index c16d0dfb88e..43e943744ae 100644 --- a/gcc/c/gimple-parser.c +++ b/gcc/c/gimple-parser.c @@ -2040,13 +2040,13 @@ c_parser_gimple_declaration (gimple_parser &parser) unsigned version, ver_offset; if (declarator->kind == cdk_id && is_gimple_reg_type (specs->type) - && c_parser_parse_ssa_name_id (declarator->u.id, + && c_parser_parse_ssa_name_id (declarator->u.id.id, &version, &ver_offset) /* The following restricts it to unnamed anonymous SSA names which fails parsing of named ones in dumps (we could decide to not dump their name for -gimple). */ && ver_offset == 0) - c_parser_parse_ssa_name (parser, declarator->u.id, specs->type, + c_parser_parse_ssa_name (parser, declarator->u.id.id, specs->type, version, ver_offset); else { diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog index 7f809547a26..5ded904a5f1 100644 --- a/gcc/testsuite/ChangeLog +++ b/gcc/testsuite/ChangeLog @@ -1,3 +1,12 @@ +2019-11-25 Joseph Myers + + * gcc.dg/gnu2x-attrs-1.c: Do not expect message about attributes + appertaining to types. + * gcc.dg/gnu2x-attrs-2.c: New test. + * g++.dg/cpp0x/gen-attrs-1.C, g++.dg/cpp0x/gen-attrs-22.C, + g++.dg/cpp0x/gen-attrs-4.C, g++.dg/cpp0x/lambda/lambda-attr1.C: + Update expected diagnostics. + 2019-11-25 Tamar Christina * gcc.dg/torture/fp-int-convert-timode-1.c: Always run if int128. diff --git a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-1.C b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-1.C index a55698c9383..c2cf912047e 100644 --- a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-1.C +++ b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-1.C @@ -1,3 +1,3 @@ // { dg-do compile { target c++11 } } -int **** [[gnu::format(printf, 1, 2)]] foo(const char *, ...); // { dg-warning "ignored" } +int **** [[gnu::format(printf, 1, 2)]] foo(const char *, ...); // { dg-warning "only applies to function types" } diff --git a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-22.C b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-22.C index 4c07df995c7..e060c523fe3 100644 --- a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-22.C +++ b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-22.C @@ -3,5 +3,5 @@ void f() { - static_cast(0); // { dg-warning "ignored" } + static_cast(0); } diff --git a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-4.C b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-4.C index 023d8396777..b401c6908e3 100644 --- a/gcc/testsuite/g++.dg/cpp0x/gen-attrs-4.C +++ b/gcc/testsuite/g++.dg/cpp0x/gen-attrs-4.C @@ -21,7 +21,7 @@ void two [[gnu::unused]] (void) {} [[gnu::unused]] int five(void) -[[noreturn]] // { dg-warning "ignored" } +[[noreturn]] // { dg-warning "does not apply to types" } { return 0; } [[noreturn]] diff --git a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-attr1.C b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-attr1.C index 9aa6506d5ed..27321f25554 100644 --- a/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-attr1.C +++ b/gcc/testsuite/g++.dg/cpp0x/lambda/lambda-attr1.C @@ -1,3 +1,3 @@ // { dg-do compile { target c++11 } } -auto l = []() [[noreturn]] {}; // { dg-warning "ignored" } +auto l = []() [[noreturn]] {}; // { dg-warning "does not apply to types" } diff --git a/gcc/testsuite/gcc.dg/gnu2x-attrs-1.c b/gcc/testsuite/gcc.dg/gnu2x-attrs-1.c index bc00371f466..87bdaec0807 100644 --- a/gcc/testsuite/gcc.dg/gnu2x-attrs-1.c +++ b/gcc/testsuite/gcc.dg/gnu2x-attrs-1.c @@ -7,8 +7,7 @@ void f (void) {}; [[gnu::alias("f")]] void g (void); /* { dg-error "only weak" "" { target *-*-darwin* } } */ -void [[gnu::alias("f")]] h (void); /* { dg-warning "ignored" } */ -/* { dg-message "that appertains to a type-specifier" "appertains" { target *-*-* } .-1 } */ +void [[gnu::alias("f")]] h (void); /* { dg-warning "does not apply to types" } */ struct [[gnu::packed]] s { int a; char b; }; _Static_assert (sizeof (struct s) == (sizeof (int) + sizeof (char))); diff --git a/gcc/testsuite/gcc.dg/gnu2x-attrs-2.c b/gcc/testsuite/gcc.dg/gnu2x-attrs-2.c new file mode 100644 index 00000000000..d512b2a2aca --- /dev/null +++ b/gcc/testsuite/gcc.dg/gnu2x-attrs-2.c @@ -0,0 +1,33 @@ +/* Test C2x attribute syntax. Test GNU attributes appertain to + appropriate constructs. Attributes on types not being defined at + the time. */ +/* { dg-do compile } */ +/* { dg-options "-std=gnu2x -Wformat" } */ + +typedef void va_type (const char *, ...); +typedef va_type [[gnu::format (printf, 1, 2)]] printf_like_1; +typedef void printf_like_2 (const char *, ...) [[gnu::format (printf, 1, 2)]]; +typedef __typeof__ (void (const char *, ...) [[gnu::format (printf, 1, 2)]]) + printf_like_3; + +va_type func1; +printf_like_1 func2; +printf_like_2 func3; +printf_like_3 func4; +va_type [[gnu::format (printf, 1, 2)]] *func5 (void); + +void +func_test (void) +{ + func1 ("%s", 1); + func2 ("%s", 1); /* { dg-warning "expects argument" } */ + func3 ("%s", 1); /* { dg-warning "expects argument" } */ + func4 ("%s", 1); /* { dg-warning "expects argument" } */ + func5 () ("%s", 1); /* { dg-warning "expects argument" } */ +} + +typedef int A[2]; + +__typeof__ (int [[gnu::deprecated]]) var1; /* { dg-warning "deprecated" } */ +__typeof__ (A [[gnu::deprecated]]) var2; /* { dg-warning "deprecated" } */ +__typeof__ (int [3] [[gnu::deprecated]]) var3; /* { dg-warning "deprecated" } */ -- 2.30.2